Owner's Manual
Table Of Contents
If
none
of
the
suggestions
below
solve
your
problem,
contact
your
nearest
JBL
service
center
or
JBL
distributor.
Problem
1 .
No
Output.
2.
Questionable
or
intermittent
output
such
as
crackling.
3.
Constant
noise
such
as
buzzing,
hissing
,
or
the
humming
sound.
4.
Poor
low
frequency
output.
Possible
Cause(s)
•
Speaker
Cable(s)
•
Amplifier
• A
poor
connection
• A
faulty
electronic
device
in
the
signal
chain
•
Poor
system
grounding
·Out-of-Polarity
Hookup
between
multiple
sp
e
akers
·
-
~-
---
Action
•
Replace
the
cable(s)
con
n
ec
t
ing
the
loudspeaker
system
and
amplifier
.
•
Make
sure
the
amplifier
channel
is
being
fed
an
input
signal
(preferably
via
a
"signal
input"
indicator
on
the
amp).
•
Check
that
the
amplifier
channel's
volume
control
is
turned
up.
_l
__
!
i
-r--
l
--1"-
--
1
•
Connect
the
speaker
and
cable
which
had
no
output
to
i
another
amplifier
channel,
making
sure
an
i
np
ut
signal
is
---~-
fed
to
the
new
amp
channel.
If
you
then
get
output,
the
l
problem
was
the
amplifier
channel.
If
not
,
then
the
----r---
problem
may
be
in
the
cable
or
speaker.
•
Check
all
cabling
for
proper
connector
contact
since
a
bad
connection
can
result
in
intermittent
contact
or
dramatically
increased
resistance
which
,
in
turn
,
can
cause
reduced
output
or
noises
unrelated
to
the
signal.
•
Since
loudspeakers
cannot
generate
these
sounds
by
themselves,
you
may
have
a
faulty
electronic
device
in
the
signal
chain.
-+--
I
-+--
!
+
l
-----r-
f
I
-+-
1
•
Check
and
correct
the
system
grounding,
as
required.
···---,-
-----r-···
•
When
two
speakers
are
hooked
up
out
-
of-polarity
("out-
of
-
phase"),
the
low
frequenc
i
es
cancel
each
other
out.
_
Try
reversing
the
polarity
of
one
of
the
speakers
either
by
turning
around
a
dual
-
banana
plug
at
the
am
plifier
or
i
---
by
reversing
the
tip/sleeve
leads
on
the
jack.
Whichever
_
___,
__
condition
results
in
greater
low-frequency
output
is
the
. ! '
in-po
,
larity
oonaition.
- . ;
I ' I . l I I
r
---
-+ t t
t-
-
--r-----
·-
-t
c·
--
-------- -. r t !
--·-·
l
---
--r--
----r - - --
..
-
~
--+--
~
--
__
:
--
-
J.
-
--
-+
----
:.
-
!-------'----
-
f--
-+------+--
·-·--+------
L-
_l
--
---
! I ! _
_j
·--
!-----+---+--
! I l ' . I '
rt
-!-
+--
-
!--
·-!--------+' - -
··--+
,_-
-------+··----+--· - - 1
u-----
---
-+----+--+--
-L-~-
~
l
I l
-·